Audit generated Ruby SDK contract and release endpoint

[replynodes-ai]

Goal

Reconcile the generated Ruby SDK with the current ReplyNodes API contract and release policy.

Scope

• Verify the vendored OpenAPI contract and generated surface against the current source of truth.
• Decide whether this SDK remains supported, is redirected to the canonical MCP, or is archived.
• Remove any retired REST endpoint/default guidance only after the replacement contract is verified.

Current safe state

The README is marked legacy and no longer contains the retired REST hostname. Runtime/generated code was not changed.

Acceptance criteria

• Exact source contract and supported base URL are documented.
• Generated code and README agree.
• Independent review verifies no stale pricing, endpoint, or read-only claims.
• Destructive archive/rename action requires owner approval.